Variometer coil and method of making same



Feb. 10. 1925. 1,525,836

- C. D. TUSKA VARIQMETER COIL AND METHOD 01- MAKING SAME Filed April 2. 1921 Patented Feb. 10, 1925.

UNITED STATES PATENT OFFICE.

CLARENCE BENTON TUSKA, F HARTFORD, CONNECTICUT, ASSIGN OB TO THE C. D.

TUSKA COMPANY, OF HARTFORD, CONNECTICUT. A CORPORATION OF CONNECT?- CUT.

VABIOMETEB COIL AND METHOD OF MAKING SAME.

Application filed April 2,

To all whomit may concern:

Be it known that I, CLARENCE D. Tusm, a citizen of the United States and resident of Hartford, county of Hartford, State oi I Connecticut, ha e invented certain new and useful Improvements in Variometer Coils and Methods of Making Same, of which the following is a specification. This invention relates to' an electric instrument for use in varying or changing the characteristics of an electric current. A de .vioe of this sort finds particular adaptabilit in the art of wireless where it may be emp oyed to vary the wave length of transl6 mitting or receiving apparatus, or for other purposes. i The aim of the invention is to provide an electrical instrument having various features of novelty and advantage and which is particularly characterized by its simplicity and economy in construction, its neatness in appearance and its effectiveness in operation. The invention is also concerned with the method of securing a coil of insulated wire to a body of insulating material.

In the accompanying drawings Fig. 1 is an elevational view, with parts in section, of an improved variometer constructed in accordance with the present invention.

Fig. 2 is taken on line 2-2 of Fig. 1. Fig. 3 is a diagrammatic view of the wirand ig. 4 is a view illustrating the method of incorporating a coil of wire in the surface of a body of insulating material.

Referring to the drawings in detail, a denotes generally the stator body comprising two blocks 10, 10 of insulating material secured together by holts 11. This body has an opening therethrough which is in. the form of a ccntralzone of a sphere. Applied to the walls of this opening is a stator winding h formed ol two coils. one in each 5 block 10.

The letter 0 denotes a rotor body of insulating material and having a spherical ierimeter to which is applied a coil or win ing d. The rotor is sup orted at diametrically so opposite points by t e trunnions 13 having bearingsrin sleeves 14, 14' mounted in regis tering notches 15 in the abutting faces of the blocks 10 On one of these trunnions is fixed a [mob 16 by means of which the rotor 1921. Serial No. 458,011.

the rotor in any position of adjustmentfand to assure a lo resistance connection, springs 17 are mounted on the trunnions forfrictional engagement with the sleeve 14 and the nut 18.

Two of the bolts the blocks 10 together, serve as binding posts through which the currentisj led to and from the windings. Inthe present instance, one end of the stator windingh is n, an' addition to tying connected to the upper right hand post 11 (referring .to Fig. 1) and the other end is connected to the right hand sleeve 14'. The

opposite ends of the rotor winding d are respcrtively connected tothe trunnions"13,.and

the sleeve H is connected by means of a wire 20 to the upper left hand bolt'll. One of the abutting' luceS- df'the blocks 10 is grooved or recessed as at .21 to accommodate the wires leading from the binding posts 11- to the Xvindings.

The present invention provides an improved method for securing the stator coils to the blocks 10. and this method will now he described with reference to Fig. 4.

The \riresforining the stator coils are, by preference, covered n ill! a suitable insulating material or fabric, such as cotton. The wire is formed into a coil of the proper shape and size by winding it onto a form (not sho n) having a surface which is complcmcntary to that of the opening in each block 1 This form will be similar to the holder .25. An insullatin material such as a gum may'then he applied to the coil to hold the several convolutions thereof in position and then the coil is transferred from the form to the holder which is positioned within u mold 26. If desired, the form may he dispensed withand the wire coiled dircrtly on the holder 9.5. The mold is filled with an insulating material in a plastic state and preferably this material has a melting point which is not greater than that of the insulating material applied to the coil. Pressure is applied to the insulating mat.- rinl. as by means of the plungers 27, to closely compact it about the coil on the holder, and then the insulating material is permitted to solidity or set. The block of in the surface thereof, may now roceeding just departly eminacoordance with the metho scribed, the stator 0011 becomes bedded in the surface of the insu ating material and the insulating material unites,

so to speak with the cotton covering of the wire so that the convolutions of the'coil are very tightly held in place, and will not become loosened or disarranged even under the rather rough usage to which vario'meters are frequently sub ected.

' of the following claims, it be' It is of course vious that the invention is susceptible/of various modifications and changes which are within the spirit of the invention without departing from the scope understood that the present disclosure of t e invention i by way of illustration only and it is not to be taken as restrictive of my conception.

I claim as my invention 1.'That improvement in the art herein described which consists in forming a concave-convex coil of wire, applyingthe coil to a holder within a mold, filling the mold with an insulating material is a pllastic state, a ressure to ear insu ating materiali all o v in g said material to solidify, and then removing the blockof insulating -n;aterial together with the coil embedded .in the surface thereof from said holder.

thereof in position, ap lying the coil to a holder within a mold, 'lling the mold with an insulating material in a plastic state, applying pressure to said insulating materia, allowing saic material to so idify, and then removing the block of insulating material together with the coil embedded in the surface thereof from said holder.

3. That improvement in the art herein described which consists in forming a coil of insulatin wire, applying a gum to the coil to hold t e convolutions thereof-imposition, applying the coil to the holder within a mold, filling the mold with an insulating nmierial whose melting point is not greater than that of the gum, applying pressure to said insulating material, allowing said material to solidify, and then removing the block of insulating material together with the coil embedded in the surface thereof from said holder and mold.

nesesse 4. That improvement in the art herein described which consists in forming a coil of insulating wire by winding the wire about a form the erimetcr of which is parti-spherical in s ape, applying a gum to the coil to hold the convolutions thereof in position, transferring the coil from the form to a holder of like shape and size as said form and positioned within a mold. filling the mold with an insulating material whose melting point is not greater than that off the gum, applying pressure to said material to compact it about the coil, permitting said material to solidify, anrlthen removing the insulating material together with the coil embedded in the surface thereof from the:

mold and holder.

5. That improvement-in the art herein described which consists'in applying a coil of fabric-covered wire in the form of a section of a 5 here to "a convex holderwithin a mold, sulati'ng material in a plastic state, applying pressure to said i'nsulatin materia allowing said material to soli ify, and then removing the block of insulating material together with the coil embedded in its concave surface from said holder.

0. That improvement in the art herein described which consists in forming apartispherical coil of insulating wire, applyi lling the mold with the ininsulating material to the coil to hold the convolutions thel'cof in position, applying the coil to a convex holder within a mold, filling the mold with an insulating material in a plastic stare, applying pressure to said.

Ibo

tcrial provided with a parti-sphericalopening, and a parti-spherical coil of fabric covered wire embedded in the walls of said opening with the material of the block united with the fabric about said wire.

CLARENCE TDENTONJIUSKA. 

